package main

import "fmt"

func main() {
	ages01 := map[string]int{
		"alice": 31,
		"bob":   13,
	}

	ages02 := make(map[string]int)
	ages02["chris"] = 20
	ages02["paul"] = 30
	m1 := make(map[string]int)
	m2 := map[string]int{}

	for name, age := range ages01 {
		fmt.Printf("%s\t%d\n", name, age)
	}
	for name, age := range ages02 {
		fmt.Printf("%s\t%d\n", name, age)
	}

	var null_map map[string]int
	empty_map := map[string]int{}
	fmt.Println(m1 != nil && m2 != nil)
	fmt.Println(len(null_map) == 0)
	fmt.Println(null_map == nil)
	fmt.Println(len(empty_map) == 0)
	fmt.Println(empty_map == nil)
	empty_map["test"] = 12
	null_map["test"] = 12

}
